AddExtensionObject, Hashtable and XSLT

[Wing]

Hi there,I try to pass the hashtable objects to XSLT using AddExtensionObject. I try to use "get_[PropertyName]()" method, it works on other properties, but not "this[object key]" in hashtable.In C#:private Hashtable ht = new Hashtable();Form form = new Form();form.type = "text";ht.add(form); XsltArgumentList xslArg = new XsltArgumentList();xslArg.AddExtensionObject("ext:ext", ht);In xslt:I tried to use "get_ht['key']", returns me nothing. If I try to use "get_ht['key']()", give me an error message, says "Expected end of the expression, found '('. ...ext:get_ht['key'] -->(<-- )"Also, how can I call a method like <xsl:value-of select="ext:get_ht[@Key].get_Type()" />, a object in the hashtable, which has a "Type" property? It will return me an error: "Expected end of the expression, found '.'. ...ext:get_ht[@Key] -->.<-- get_Type()"...By the way, how can I use "xsl:for-each" for "get_Keys()" method? <xsl:for-each select ="ext:get_Keys()"> returns an error message as "Expression must evaluate to a node-set."Thanks a lotWing

[boen_robot]

What does ext:get_Keys() return? As noted by the error message, you can't use it unless it returns a node set. If you're able to value it off, chances are it's a simple string.As for the ext:get_ht() method, it seems it could be a syntax error. After all, "[]" mean predicates in XPath, and an expression isn't expected to start right after one. Try ext:get_ht('key') instead (and ext:get_ht(@Key).get_Type() respectively).

[Wing]

get_Keys() should returns a Collection of Keys from the hashtable. They will be a set of strings. I am not sure how to make them to a node set.I tried ext:get_ht('key'), returns me an error message: " 'get_ValidationFields()' is an unknown XSLT function."...If I changed "ext:get_ht[@Key].get_Type()" to "ext:get_ht(@Key).get_Type()", it still returns me the same error message: "Expected end of the expression, found '.'. ...ext:get_ht[@Key] -->.<-- get_Type()"... It doesn't seem like the ".".Does "[", "]" and "." can be instead somehow in XSLT?Thanks a lotWing

[boen_robot]

The problem is all of those have another meaning in XPath, and inherently, in XSLT. "[" and "]" encompass a predicate, and "." can be a part of an element's name, a decimal separator in a number or... I'm not sure what. So, when you have "ext:get_ht['key']", you're really requesting the ext:get_ht element at the current XPath context (as far as the predicate goes - a simple string would always evaluate to true, so it's like you have nothing).There are no objects in XPath, and thus function().something() is not a valid construction. You'll have to resrtict yourself as to not use objects. Arrays are also non-existent, but there should be some way in C# by which you can map them into node-sets, as node-sets are just that - an array of XPath nodes (and inside each node there can be another node-set or a string, sometimes easily translatable into a number or a boolean).I'm not aware of the XSLT processor API you're using, but bottom line is you must manually translate C# functions into XPath functions, and XPath functions can only return node-sets, strings, numbers or booleans. If the method returns an array or object, you'll have to manually create another function that turns the other function's output into one of the XPath types.

[aalbetski]

this may work for you, I found the trick to be to add the hashtable in the constructor for the class rather than try and pass it through as a object. I then invoke the getht method passing it a key value. At this time I hard-wired it just to get it working, but it may be enough to get you kick started.NET console app code

using System;using System.Collections;using System.Collections.Generic;using System.Text;using System.IO;using System.Xml;using System.Xml.XPath;using System.Xml.Xsl;namespace ConsoleApplication5{		class Program		{				static void Main(string[] args)				{						XslCompiledTransform xslt = new XslCompiledTransform();						xslt.Load("XSLTFile1.xslt");						XPathDocument doc = new XPathDocument("XMLFile1.xml");						XsltArgumentList xslArg = new XsltArgumentList();						Hashtable myHash = new Hashtable();						myHash.Add("1", "test1");						myHash.Add("2", "test2");						ht myht = new ht(myHash);						xslArg.AddExtensionObject("ext:ht", myht);						xslt.Transform("XMLFile1.xml", xslArg, XmlWriter.Create("output.xml"));				}				public class ht				{						Hashtable hh;						public ht(Hashtable ht)						{								hh = ht;						}						public string getht(string key)						{								return hh[key].ToString();						}				}		}}

XSLT File

<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"  xmlns:myHT="ext:ht">	<xsl:template match="/">		<top>			<xsl:value-of select="myHT:getht('1')" />		</top>	</xsl:template></xsl:stylesheet>

The content of XML file is not used here, but here it is for this example

<xml>	</xml>

Resulting Output file

<?xml version="1.0" encoding="utf-8"?><top xmlns:myHT="ext:ht">test1</top>

[Wing]

Thanks a lot guys,I made my way around it by creating node set in C#...If only I knew XSLT won't take array or list of objects earlier, then I won't waste my two weeks time on it...Thank you very muchWing

[Wing]

Thanks a lot guys,I made my way around it by creating node set in C#...If only I knew XSLT won't take array or list of objects earlier, then I won't waste my two weeks time on it...Thank you very muchWing